National Highways’ M3 Junction 9 scheme in South Hampshire is advancing from this weekend as a series of beam lifts gets underway.

National Highways is closing the motorway between junction 8 and junction 9 in both directions from 9pm this evening, 30 January to 6am on Monday 2 February so steel beams for a new roundabout at Junction 9 can be installed on the north side of the junction.

This process will be repeated over another weekend closure from 13 to 16 February, to install the 40m, 100t beams at the south side of the junction.

The steel beams are key to the construction of new bridge decks for the redesigned roundabout and junction layout. They form the structure for two new bridges on the roundabout, required to create a ‘dumbbell’ layout that improves traffic flow by replacing signal-controlled intersections with two smaller, linked roundabouts. This design will enable continuous movement by eliminating the need for traffic to stop completely.

Once the beams are in place, construction on the new roundabout will continue over the coming months, before fully opening to traffic in summer 2028.

Scheme vision

The M3 junction 9 improvements – which received a £290M funding pledge from the government last March – are designed to  alleviate congestion and improve safety, with completion expected by 2028. VolkerFitzpatrick was appointed as the principal contractor for the scheme in 2022,

The enhancements will remove the need for through traffic to use the roundabout by creating direct, uninterrupted linkages between the M3 and the A34. The changes also involve widening the M3 from three to four lanes to enable the dedicated A34 links to be established and facilitate freight travelling from the port to the midlands and beyond.

The upgrade is designed to support the building of 2,000 new homes in Winchester and improve reliability for drivers – with peak time journeys targeted to be almost 30 per cent faster through the junction to the A272.

Between the M3 and A34, drivers will save more than 20 per cent of their overall journey time during peak hours.

The project will also provide environmental benefits, including more than 8.9ha of chalk grassland, as well as new routes for walkers, cyclists and horse riders.

National Highways senior project manager Tom Beasley said: “This junction is a key interchange for economic growth, connecting the ports of Southampton and Portsmouth to the rest of the country, and allowing millions of tonnes of freight to be shipped.

“It also provides a vital route for those travelling to the south coast, whether that’s for business or leisure.

“Changing the layout of the roundabout is fundamental to improving those links, and installing the first bridge beams this weekend marks a major milestone for the scheme.

“To do that safely, we need to close this stretch of the motorway and advise anyone travelling through the area to plan their journeys carefully and allow extra time where possible.”

Detractors

While Hampshire County Council, Hampshire’s Chamber of Commerce and Associated British Ports have welcomed the scheme as an economic enabler, it has met with criticism from campaign group Transport Action Network (TAN), which questioned how the original £200M cost of the project had “rocketed”.

On the scheme’s £290M funding pledge, TAN director Chris Todd remarked that the original funding figures presented to the examination and the secretary of state included inflation and other risks, indicating that “National Highways is hiding the true cost of its schemes in order to get them approved, or is incredibly bad at its job.”

“The cost increases seen here will deny much needed investment in road maintenance and public transport elsewhere,” he said.

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